Epoxy resin curable composition and adhesive containing the same

Abstract

Provided is an epoxy resin curable composition that cures quickly and has high hardness and exceptional color tone after curing. Provided is an epoxy resin curable composition containing an epoxy resin having two or more epoxy groups per molecule, a thiol compound having two or more thiol groups per molecule, an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group, the epoxy resin curable composition being characterized in that the molar ratio M1+2 / Me is 0.11-0.5 and the molar ratio M3 / Me is 0.005-0.1, where Me is the number of moles of epoxy groups included in the epoxy resin curable composition, M1+2 is the total number of moles of primary amino groups and secondary amino groups, and M3 is the number of moles of tertiary amino groups.

Description

Technical Field

[0001] The present invention relates to an epoxy resin curable composition that can provide a cured product with fast curing, high hardness after curing, strong adhesive strength, and excellent color tone.

Background Art

[0002] Conventionally, epoxy resins have good adhesiveness, chemical resistance, and physical properties, and are widely used as adhesives and the like. A method of adding a thiol compound as a curing agent and amines as a curing accelerator is known for applications that require fast curing and high adhesive strength.

[0003] As compounds that can rapidly react thiol groups and epoxy groups, many terminal thiol group-containing compounds that do not contain a polysulfide skeleton in the main chain have been reported (for example, see Patent Document 1). Among them, as a curing agent for epoxy resins that combines economy and safety, compounds having a polyether skeleton in the main chain and having three or more thiol groups in one molecule are widely commercially available. Examples of compounds having a polyether skeleton in the main chain and having three or more thiol groups in one molecule include "Polythiol QE-340M" manufactured by Toray Fine Chemical Co., Ltd., "Capcure 3-800" and "GPM-800" manufactured by Gabriel Performance Products.

[0004] As amines widely used as curing accelerators for thiol groups and epoxy groups, tertiary amines such as 2,4,6-tris(dimethylaminomethyl)phenol (manufactured by Evonik Corporation, ANCAMINE K-54), N,N-dimethylpropylamine, and bis(2-dimethylaminoethyl)ether can be mentioned.

[0005] However, conventionally known epoxy resin curable compositions turn yellow and become colored when cured, so there is a problem in applications that require a nearly colorless and excellent color tone, such as adhesives for glass and adhesives for decorative products.

[0006] Conventional colorless epoxy resin curable compositions have slow curing times, making them unsuitable for applications requiring rapid curing, and their hardness and adhesive strength are not always sufficient. Thus, it has been difficult to achieve a combination of rapid curing, hardness, adhesive strength, and color in epoxy resin curable compositions consisting of epoxy resin, thiol compounds, and amine compounds. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 8-269203 [Overview of the project] [Problems that the invention aims to solve]

[0008] The present invention provides an epoxy resin curable composition that cures quickly, has high hardness after curing, strong adhesive strength, and excellent color tone. [Means for solving the problem]

[0009] The epoxy resin curable composition of the present invention is an epoxy resin curable composition comprising an epoxy resin having two or more epoxy groups in one molecule, a thiol compound having two or more thiol groups in one molecule, an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group, wherein the number of moles of epoxy groups contained in the epoxy resin curable composition is Me, and the total number of moles of the primary amino group and secondary amino group is M. 1+2 When the number of moles of tertiary amino groups is M3, the molar ratio M 1+2 It is characterized by having a ratio of / Me of 0.11 to 0.5 and a molar ratio of M3 / Me of 0.005 to 0.1. [Effects of the Invention]

[0010] The epoxy resin curable composition of the present invention exhibits rapid curing, high hardness and strong adhesive strength after curing, and excellent color tone.

[0011] When the epoxy resin curable composition of the present invention is used as an adhesive, it exhibits strong adhesion to various substrates such as metals and glass. This epoxy resin curable composition can be used as an adhesive, sealant, potting agent, coating agent, resin modifier, and the like.

[0012] In particular, the epoxy resin curable composition of the present invention is ideal for use as an adhesive for glass, an adhesive for decorative items, an adhesive for watch parts, an electrical and electronic adhesive, an electrical and electronic potting material, and an adhesive for general carpentry, due to its excellent color tone. [Modes for carrying out the invention]

[0013] The epoxy resin curable composition of the present invention contains an epoxy resin having two or more epoxy groups in one molecule, a thiol compound having two or more thiol groups in one molecule, an amine compound A having a primary amino group and / or a secondary amino group, and an amine compound B having a tertiary amino group.

[0014] Examples of epoxy resins having two or more epoxy groups in one molecule include epoxy resins obtained by adding epichlorohydrin to polyhydric phenols such as bisphenol A, bisphenol F, resorcinol, hydroquinone, pyrocatechol, 4,4-dihydroxybiphenyl, and 1,5-hydroxynaphthalene; epoxy resins obtained by adding epichlorohydrin to polyhydric alcohols such as ethylene glycol, propylene glycol, and glycerin; epoxy resins obtained by adding epichlorohydrin to aromatic dicarboxylic acids such as oxybenzoic acid and phthalic acid; and polysulfide polymers having epoxy groups at the ends (product names "FLEP-50" and "FLEP-60," both manufactured by Toray Fine Chemicals Co., Ltd.). From the viewpoint of workability and suppression of poor mixing, epoxy resins having two or more epoxy groups in one molecule are preferably liquid at room temperature. Examples of epoxy resins having two or more epoxy groups in one molecule include jER-828 (trade name, manufactured by Mitsubishi Chemical Corporation), DER-331 (trade name, manufactured by Dow Chemical), jER-825 (trade name, manufactured by Mitsubishi Chemical Corporation), jER-827 (trade name, manufactured by Mitsubishi Chemical Corporation), jER-806 (trade name, manufactured by Mitsubishi Chemical Corporation), and jER-807 (trade name, manufactured by Mitsubishi Chemical Corporation).

[0015] Epoxy resins having two or more epoxy groups per molecule are preferably those with an epoxy equivalent of 50 to 1000 g / eq. More preferably, epoxy resins having two or more epoxy groups per molecule have an epoxy equivalent of 100 to 300 g / eq.

[0016] Examples of thiol compounds containing two or more thiol groups in one molecule include ethylene glycol bis(3-mercaptopropionate), diethylene glycol bis(3-mercaptopropionate), tetraethylene glycol bis(3-mercaptopropionate), 1,2-propylene glycol bis(3-mercaptopropionate), diethylene glycol bis(3-mercaptobutyrate), 1,4-butanediol bis(3-mercaptopropionate), and 1,4-butanediol bi (3-mercaptobutyrate), 1,8-octanediolbis(3-mercaptopropionate), 1,8-octanediolbis(3-mercaptobutyrate), hexanediolbisthioglycolate, trimethylolpropantris(3-mercaptopropionate), trimethylolpropantris(3-mercaptobutyrate), trimethylolpropantris(3-mercaptoisobutyrate), trimethylolpropantris(2-mercaptoisobutyrate), trimethylol Ropant tristhioglycolate, tris-[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, trimethylolethanetris(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptoisobutyrate), pentaerythritol tetrakis(2-mercaptoisobutyrate), dipentaerythritol hexakis( Examples include 3-mercaptopropionate, dipentaerythritol hexakis(2-mercaptopropionate), dipentaerythritol hexakis(3-mercaptobutyrate), dipentaerythritol hexakis(3-mercaptoisobutyrate), dipentaerythritol hexakis(2-mercaptoisobutyrate), pentaerythritol tetrakisthioglycolate, dipentaerythritol hexakisthioglycolate, and thiol compounds having a polyether moiety in the main chain.

[0017] The thiol compound preferably has three or more thiol groups in one molecule. Examples of such thiol compounds include trimethylolpropanetris (3-mercaptopropionate), pentaerythritoltetrakis (3-mercaptopropionate), trimethylolethanetris (3-mercaptobutyrate), and pentaerythritoltetrakis (3-mercaptoacetate).

[0018] A thiol compound containing two or more thiol groups in one molecule preferably has a polyether moiety in its main chain, and preferably has a thiol group on a carbon adjacent to a carbon having a hydroxyl group. Furthermore, it is preferable that the thiol compound does not have a carbonyl group. The absence of a carbonyl group in the thiol compound is preferable because it suppresses hydrolysis of the cured product and improves its water resistance.

[0019] A structure having a polyether moiety in the main chain is preferably represented by the following general formula (1), and the terminal thiol group is preferably represented by the following formula (2). [ka] (However, R 1 R is a residue obtained by removing m hydrogen atoms from a polyhydric amine or polyhydric alcohol with 10 or fewer carbon atoms, 2 (where n is an alkylene group with 2 to 4 carbon atoms, n is an integer from 1 to 200, and m is an integer from 2 to 8.) [ka]

[0020] In the above general formula (1), R 1The residue is obtained by removing m hydrogen atoms from a polyhydric amine or polyhydric alcohol having 10 or fewer carbon atoms. Examples of polyhydric amines or polyhydric alcohols having 10 or fewer carbon atoms include glycerin, trimethylolpropane, trimethylolethane, hexanetriol, diglycerin, pentaerythritol, triethanolamine, ethylenediamine, and sucrose. These polyhydric amines and polyhydric alcohols may be used alone or in combination. Among the above polyols, glycerin, trimethylolpropane, and trimethylolethane are particularly preferred.

[0021] In the above general formula (1), R 2 This refers to an alkylene group having 2 to 4 carbon atoms. Examples of alkylene groups having 2 to 4 carbon atoms include ethylene, n-propylene, isopropylene, n-butylene, and isobutylene.

[0022] In the general formula (1) above, n is an integer between 1 and 200, preferably between 1 and 100. Also, m is an integer between 2 and 8, preferably between 2 and 5.

[0023] Examples of thiol compounds having the structures represented by the general formulas (1) and (2) above include "Polythiol QE-340M" manufactured by Toray Fine Chemicals Co., Ltd., and "Capcure3-800" and "GPM-800" manufactured by Gabriel Performance Products. These thiol compounds do not contain a carbonyl group.

[0024] A thiol compound containing two or more thiol groups in one molecule preferably has at least one thiol group represented by formula (2), and more preferably has two or more. In a thiol compound, all thiol groups may be contained in the structure represented by formula (2).

[0025] A thiol compound containing two or more thiol groups in one molecule preferably has a thiol group content of 1 to 50% by mass, and more preferably has a thiol group content of 5 to 20% by mass.

[0026] The statement that a thiol compound does not have a carbonyl group means that the thiol compound does not have a carbonyl group, carboxyl group, thiocarboxyl group, aldehyde group, ester bond, thioester bond, amide bond, etc.

[0027] The epoxy resin and thiol compound described above can be formulated in such a way that the molar ratio Mt / Me (mole of thiol groups derived from the thiol compound to moles of epoxy groups derived from the epoxy resin, Mt to Me) in the epoxy resin curable composition is preferably 0.1 to 0.9, more preferably 0.2 to 0.8, even more preferably 0.2 to 0.7, and even more preferably 0.32 to 0.64. A molar ratio Mt / Me of 0.1 or higher is preferable because it speeds up curing. A molar ratio Mt / Me of 0.9 or lower is preferable because it increases the Shore D hardness of the cured product.

[0028] The amount of thiol compound blended can be appropriately designed depending on the physical properties of the epoxy resin curable composition, and preferably it is such that the above molar ratio Mt / Me relationship is satisfied. For example, it is preferable to blend 50 to 150 parts by mass of thiol compound with 100 parts by mass of epoxy resin having two or more epoxy groups in one molecule. When the amount of thiol compound is 50 to 150 parts by mass with 100 parts by mass of epoxy resin, the epoxy resin curable composition hardens quickly, has high hardness of the cured product, and has sufficient adhesive strength. The amount of thiol compound blended with 100 parts by mass of epoxy resin is more preferably 60 to 120 parts by mass, and even more preferably 70 to 100 parts by mass.

[0029] The epoxy resin curable composition contains amine compound A having a primary amino group and / or a secondary amino group, and amine compound B having a tertiary amino group. By containing at least two amine compounds consisting of amine compound A and amine compound B, the epoxy resin curable composition can achieve rapid curing, high hardness after curing, strong adhesive strength, and excellent color tone. Amine compound A may have only a primary amino group derived from a primary amine, only a secondary amino group derived from a secondary amine, or a primary amino group derived from a primary amine and a secondary amino group derived from a secondary amine.

[0030] Amine compound A is preferably an aliphatic amine. Examples of aliphatic amines include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,5-diaminopentane, hexamethylenediamine, tetramethylenediamine, trimethylhexamethylenediamine, 2-methyl-1,5-diaminopentane, polyetherdiamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, bis(hexamethylene)triamine, N,N'-dimethylethylenediamine, N,N-dimethyl-1,3-propanediamine, etc. It is preferable that amine compound A is not an amine in which the amino group of the aliphatic amine is composed only of secondary amino groups. That is, it is preferable that amine compound A has at least one primary amino group. It is also preferable that it does not have a tertiary amino group.

[0031] Amine compound A is more preferably an amine having two or more primary amino groups and / or secondary amino groups in one molecule, and no tertiary amino groups. Examples of amine compound A include ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,5-diaminopentane, hexamethylenediamine, tetramethylenediamine, trimethylhexamethylenediamine, 2-methyl-1,5-diaminopentane, polyetherdiamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, bis(hexamethylene)triamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, and bis(hexamethylene)triamine. Amines having two or more amino groups in one molecule and not having a tertiary amino group in the molecule are more preferably ethylenediamine, diethylenetriamine, triethylenetetramine, 1,3-diaminopropane, and tetraethylenepentamine.

[0032] Amine compound A more preferably has three or more primary amino groups and / or secondary amino groups in one molecule. Amines having three or more amino groups in one molecule include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, and bis(hexamethylene)triamine, with triethylenetetramine being even more preferred.

[0033] Amine compound A is particularly preferably a modified product derived from an amine having three or more primary amino groups and / or secondary amino groups in one molecule. Among modified products derived from amines having three or more amino groups in one molecule, modified diethylenetriamine, modified triethylenetetramine, and modified tetraethylenepentamine are particularly preferred, with modified products obtained by reacting the amino groups of triethylenetetramine with a mono- or polyepoxy compound being more preferred. An example of a modified product derived from an amine having three or more amino groups in one molecule is "BB-AMINE 3138" manufactured by BB RESINS SRL.

[0034] The modified product, which uses an amine having three or more amino groups in one molecule as a raw material, preferably has an amine value of 500 to 2500 KOH mg / g, and more preferably has an amine value of 800 to 1700 KOH mg / g.

[0035] Amine compound B is an amine having a tertiary amino group derived from a tertiary amine. Examples of amine compound B include trimethylamine, benzyldimethylamine, N,N,N′,N′-tetramethylethylenediamine, N,N,N′,N′-tetramethyl-1,3-diaminopropane, dimethylaniline, N,N-dimethyl-1,3-propanediamine, diazabicycloundecene, 2,4,6-tris(dimethylaminomethyl)phenol, ANCAMINE® K-54 (manufactured by Evonik), and N,N′-bis(3-(dimethylamine)propylurea). Amine compound B is preferably an amine having two or more tertiary amino groups derived from a tertiary amine. More preferably, it does not have a primary amino group derived from a primary amine. Even more preferably, it has only tertiary amino groups derived from a tertiary amine and does not have a primary amino group derived from a primary amine or a secondary amino group derived from a secondary amine. By including amine compound B, the hardness of the cured product can be increased and the adhesive strength can be increased.

[0036] The amine compound A is the molar ratio M of the total number of moles M of primary amino groups and secondary amino groups to the number of moles Me of epoxy groups derived from the epoxy resin present in the epoxy resin curable composition. 1+2 The blending amount can be determined so that M 1+2 / Me is 0.11 to 0.5. The molar ratio M 1+2 / Me is preferably 0.15 to 0.5, more preferably 0.2 to 0.5, and even more preferably 0.27 to 0.50. By making the molar ratio M 1+2 / Me 0.11 or more, the color tone of the cured product becomes excellent, which is preferable. Also, by making the molar ratio M 1+2 / Me 0.5 or less, the Shore D hardness of the cured product increases, which is preferable.

[0037] The blending amount of the amine compound B can be determined so that the molar ratio M3 / Me of the number of moles M3 of the tertiary amino group to the number of moles Me of the epoxy groups derived from the epoxy resin present in the epoxy resin curable composition is 0.005 to 0.1. The molar ratio M3 / Me is preferably 0.01 to 0.095, more preferably 0.015 to 0.09, even more preferably 0.015 to 0.085, and even more preferably 0.02 to 0.08. By making the molar ratio M3 / Me 0.005 or more, the Shore D hardness of the cured product increases, which is preferable. Also, by making the molar ratio M3 / Me 0.1 or less, the color tone of the cured product becomes excellent, which is preferable.

[0038] The molar ratio M3 / M of the number of moles M3 of the tertiary amino group to the total number of moles M of the primary amino group and the secondary amino group present in the epoxy resin curable composition for the amine compound A and the amine compound B 1+2 is preferably 0.04 to 1.1. The molar ratio M3 / M 1+2 is more preferably 0.04 to 1.0, even more preferably 0.04 to 0.7, and even more preferably 0.04 to 0.4. By making the molar ratio M3 / M 1+2 0.04 or more, the Shore D hardness of the cured product increases, which is preferable. Also, by making the molar ratio M3 / M 1+2 0.04 or more, the Shore D hardness of the cured product increases, which is preferable. Also, by making the molar ratio M3 / M 1+2By reducing this to 1.1 or less, the color tone of the cured product becomes superior, which is preferable.

[0039] The proportions of amine compound A and amine compound B can be appropriately designed depending on the physical properties of the cured product, and the above molar ratio M 1+2 The relationship between / Me and M3 / Me is satisfied, preferably with a molar ratio of M3 / M 1+2 The relationship is to be satisfied. For example, it is preferable to blend 1 to 30 parts by mass of amine compound A with 100 parts by mass of epoxy resin having two or more epoxy groups in one molecule. When the amount of amine compound A is 1 to 30 parts by mass with 100 parts by mass of epoxy resin, a cured product can be obtained that hardens quickly, has sufficient adhesive strength, and also has excellent color matching properties. The amount of amine compound A blended with 100 parts by mass of epoxy resin is more preferably 2 to 30 parts by mass, and even more preferably 5 to 30 parts by mass.

[0040] For example, 0.5 to 10 parts by mass of amine compound B is preferably blended with 100 parts by mass of epoxy resin having two or more epoxy groups in one molecule. When 0.5 to 10 parts by mass of amine compound B is added per 100 parts by mass of epoxy resin, a cured product with high Shore D hardness and excellent color tone can be obtained. The amount of amine compound B blended per 100 parts by mass of epoxy resin is more preferably 1 to 9 parts by mass, and even more preferably 1 to 7 parts by mass.

[0041] The epoxy resin curable composition of the present invention cures at room temperature. The epoxy resin curable composition exhibits excellent coloration after curing, being close to colorless and / or white. In this invention, "excellent color tone" refers to the L of a cured product with a thickness of 8 mm. * a * b * chromaticity a in a color system * The range is -10 to +10, and b * The range is -20 to +20. Chromaticity a * If the temperature is outside the range of -10 to +10, the color becomes darker. The epoxy resin curing composition is preferably L of a cured product with a thickness of 8 mm. * a * b* chromaticity a in a color system * However, it ranges from -9 to +9, and b * The temperature range is -17 to +19. The epoxy resin curing composition is more preferably the L of a cured product with a thickness of 8 mm after curing for 24 hours at 23°C and 50% RH. * a * b * chromaticity a in a color system * However, it ranges from -8 to +8, and b * The range is -15 to +19. The color of the cured product is a * The color of the cured product is more preferably -8 to +5, and even more preferably -7 to +1. * More preferably, the range is -10 to +19, even more preferably -7 to +19, and particularly preferably -5 to +19.

[0042] The epoxy resin curing composition has a cured product with a thickness of 8 mm and a color tone of L * a * b * In the color space of a color system, lightness L * It is preferably 50 or more, more preferably 55 or more, and even more preferably 60 or more.

[0043] Said L * a * b * A color space is a method of representing color, established by the International Commission on Illumination (CIE) in 1976. It physically measures the amount of color light stimulation that causes color perception, and uses lightness (L). * Value), degree of magenta and green (a * Value), degree of yellow and blue (b * The value is displayed as L. * A value of 0 represents black, and a value of 100 represents white. * If the value is negative, it represents a color closer to green, and if the value is positive, it represents a color closer to red, as described in b * A negative value indicates a color closer to blue, while a positive value indicates a color closer to yellow.

[0044] Said L * a * b *The method for measuring color space is determined by using a colorimeter (for example, the "CR-300" colorimeter manufactured by Minolta Corporation), which is a measuring device specified in the Japanese Industrial Standard JIS Z 8781-4:2013.

[0045] The epoxy resin curable composition preferably has a curing time of 1 to 20 minutes. More preferably, the curing time of the epoxy resin curable composition, when curing 10 g of the epoxy resin curable composition at 23°C and 50% RH, is 1 to 15 minutes, and even more preferably 1 to 10 minutes. A curing time of 1 to 15 minutes is preferable as it is suitable for applications requiring rapid curing.

[0046] The curing time was measured based on the method for determining the pot life of multi-component adhesives (Method 1) described in JIS K 6870. Under conditions of 23°C and 50% RH, 10 g of epoxy resin was mixed with a thiol compound and an amine compound in the specified proportions. The curing time was defined as the point at which a toothpick inserted into the epoxy resin curable composition became immobile.

[0047] When the epoxy resin curable composition is applied to a thickness of 6.0 mm or more and cured at 23°C and 50% RH, it is preferable that the Shore D hardness according to JIS K7215 is 75 or higher 3 hours after the start of curing, and that the Shore D hardness according to JIS K7215 is 75 or higher 24 hours after the start of curing. A Shore D hardness of 75 or higher 3 hours after the start of curing is preferable as it results in a cured product with strong adhesive strength. The Shore D hardness after 3 hours after the start of curing is more preferably 76 to 88, and even more preferably 77 to 85. Furthermore, a Shore D hardness of 75 or higher 24 hours after the start of curing is preferable as it results in a cured product with strong adhesive strength. The Shore D hardness after 24 hours after the start of curing is more preferably 76 to 83, and even more preferably 78 to 84.

[0048] The epoxy resin curable composition may further contain fillers, plasticizers, flexibility-imparting agents, coupling agents, antioxidants, thixotropy-imparting agents, dispersants, etc., to the extent that they do not hinder the objectives of the present invention.

[0049] The epoxy resin curable composition of the present invention can be used as an adhesive that adheres well to metals, glass, stone, concrete, etc., and has excellent color tone. Adhesives containing this epoxy resin curable composition are suitable for use as, for example, adhesives for iron plates, glass, decorative items, watch parts, and general-purpose carpentry adhesives, and are particularly suitable for use as adhesives for glass, decorative items, watch parts, and general-purpose carpentry adhesives. [Examples]

[0050] Examples and comparative examples are shown below. In the following examples, unless otherwise specified, the raw materials used were general reagents purchased from reagent manufacturers. The following apparatus and methods were used for the analysis.

[0051] ·Curing time The curing time of the epoxy resin curable composition was defined as the point at which a toothpick inserted into the epoxy resin curable composition became immobile, based on the method for determining the pot life of multi-component adhesives described in JIS K 6870 (Method 1). Specifically, under conditions of 23°C and 50% RH, a toothpick was inserted into the epoxy resin curable composition obtained by mixing the raw materials for each example, and the point at which the toothpick became immobile was measured as the curing time. The curing time was measured from the start of mixing, and the state of the toothpick was checked every 30 seconds to determine the time in minutes. For Examples 1-7 and Comparative Examples 1-11, 10 g of epoxy resin was mixed with thiol compounds, amine compound A, and amine compound B in the proportions shown in Tables 1 and 2.

[0052] • Hardness (Shore D hardness) The hardness of the epoxy resin curable composition was measured according to the method specified in JIS K 7215. Specifically, the epoxy resin curable composition was poured into multiple containers with an inner diameter of 31 mm and a depth of 8 mm in a room at a temperature of 23°C and a humidity of 50% RH. Starting from the beginning of mixing of the epoxy resin curable composition, measurement samples of 31 × 8 mm in diameter were obtained at 3 hours and 24 hours later. The flat surface of the sample was measured using a Type D durometer. Measurements were performed three times for each measurement sample, and the average value was taken as the hardness value.

[0053] • Brightness and chromaticity The lightness and chromaticity of the epoxy resin cured product were measured. Specifically, using a colorimeter (Minolta "CR-300") specified in JIS Z 8781-4, the epoxy resin curable composition for each example was placed in a container with an inner diameter of 31 mm and a depth of 8 mm and cured at 23°C and 50% RH. After 24 hours, the epoxy resin cured product was removed from the container, and the lightness L of the 8 mm thick epoxy resin cured product was measured. * , chromaticity a * , chromaticity b * The chromaticity a was measured at room temperature. * and b * The measurement results are shown in Tables 1 and 2.

[0054] Example 1 Under conditions of 23°C and 50% RH, 10 g (100 parts by mass) of "jER828" (bisphenol A type epoxy resin, epoxy equivalent of 184-194 g / eq) manufactured by Mitsubishi Chemical Corporation, which has two or more epoxy groups per molecule, 8.8 g (88 parts by mass) of "Polythiol QE-340M" manufactured by Toray Fine Chemicals Co., Ltd., which has two or more thiol groups per molecule, 0.8 g (8 parts by mass) of "BB-AMINE 3138" manufactured by BB RESINS SRL, which has a primary amine and / or a secondary amine as amine compound A, and 0.4 g (4 parts by mass) of "EHC-30" manufactured by ADEKA, which has a tertiary amine as amine compound B, were mixed with a spatula for 15 seconds to obtain an epoxy resin curable composition. Note that Me represents the number of moles of epoxy groups in the epoxy resin curable composition, Mt represents the number of moles of thiol groups, and M represents the total number of moles of primary and secondary amines in amine compound A. 1+2 The number of moles M3 of the tertiary amine and the molar ratio M3 are listed in Table 1. 1+2 / Me, M3 / Me, M3 / M 1+2 The Mt / Me ratio was calculated and recorded.

[0055] When the curing time at 23°C was measured using the obtained epoxy resin curable composition, it cured in 6 minutes. Furthermore, the Shore D hardness was 78 after 3 hours from the start of curing, and 80 after 24 hours from the start of curing. In addition, when the chromaticity of the cured product of the epoxy resin curable composition was measured, the chromaticity a * -6, b * The result was 18. These results are shown in Table 1.

[0056] Example 2 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.6 g (86 parts by mass), amine compound A to 1.1 g (11 parts by mass), and amine compound B to 0.3 g (3 parts by mass).

[0057] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 5 minutes. Furthermore, the Shore D hardness was 78 after 3 hours from the start of curing, and 80 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -6, b * The result was 19. These results are shown in Table 1.

[0058] Example 3 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.7 g (87 parts by mass), amine compound A to 1.1 g (11 parts by mass), and amine compound B to 0.2 g (2 parts by mass).

[0059] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 5 minutes. Furthermore, the Shore D hardness was 79 after 3 hours from the start of curing, and 79 after 24 hours from the start of curing. In addition, the chromaticity of the cured product of the epoxy resin curable composition was measured, and the chromaticity a * -6, b * The result was 17. These results are shown in Table 1.

[0060] Example 4 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.9 g (89 parts by mass), amine compound A to 0.9 g (9 parts by mass), and amine compound B to 0.2 g (2 parts by mass).

[0061] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 6 minutes. Furthermore, the Shore D hardness was 77 after 3 hours from the start of curing, and 80 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -6, b * The result was 16. These results are shown in Table 1.

[0062] Example 5 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.9 g (89 parts by mass) and amine compound B was changed to 0.3 g (3 parts by mass).

[0063] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 6 minutes. Furthermore, the Shore D hardness was 78 after 3 hours from the start of curing, and 80 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -6, b * The result was 18. These results are shown in Table 1.

[0064] Example 6 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that amine compound A was changed to 1.5 g (15 parts by mass) and amine compound B was changed to 0.1 g (1 part by mass).

[0065] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 4 minutes. Furthermore, the Shore D hardness was 78 after 3 hours from the start of curing, and 76 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -5, b * The result was 14. These results are shown in Table 1.

[0066] Example 7 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 4.4 g (44 parts by mass), amine compound A to 1.5 g (15 parts by mass), and amine compound B to 0.1 g (1 part by mass).

[0067] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 5 minutes. Furthermore, the Shore D hardness was 84 after 3 hours from the start of curing, and 83 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -6, b * The result was 17. These results are shown in Table 1.

[0068] Comparative Example 1 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.9 g (89 parts by mass), amine compound A to 1.1 g (11 parts by mass), and amine compound B was not included.

[0069] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 6 minutes. Furthermore, the Shore D hardness was 72 after 3 hours from the start of curing, and 73 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -5, b * The result was 7. These results are shown in Table 1.

[0070] Comparative Example 2 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 8.9 g (89 parts by mass), amine compound B to 1.1 g (11 parts by mass), and amine compound A was not included.

[0071] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 5 minutes. Furthermore, the Shore D hardness was 82 after 3 hours from the start of curing, and 83 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -8, b * The result was 37. These results are shown in Table 1.

[0072] Comparative Example 3 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that amine compound A was changed to 1.5 g (15 parts by mass) and amine compound B to 0.6 g (6 parts by mass).

[0073] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 4 minutes. Furthermore, the Shore D hardness was 80 after 3 hours from the start of curing, and 78 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -5, b * The result was 22. These results are shown in Table 2.

[0074] Comparative Example 4 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that amine compound A was changed to 0.3 g (3 parts by mass) and amine compound B to 0.6 g (6 parts by mass).

[0075] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 7 minutes. Furthermore, the Shore D hardness was 82 after 3 hours from the start of curing, and 81 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -8, b * The result was 23. These results are shown in Table 2.

[0076] Comparative Example 5 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that amine compound A was changed to 0.3 g (3 parts by mass) and amine compound B to 0.1 g (1 part by mass).

[0077] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 15 minutes. Furthermore, the Shore D hardness was 46 after 3 hours from the start of curing, and 63 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -6, b * The result was 12. These results are shown in Table 2.

[0078] Comparative Example 6 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 13.2 g (132 parts by mass), amine compound A to 1.5 g (15 parts by mass), and amine compound B to 0.6 g (6 parts by mass).

[0079] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 5 minutes. Furthermore, the Shore D hardness was 29 after 3 hours from the start of curing, and 32 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -3, b * The result was 15. These results are shown in Table 2.

[0080] Comparative Example 7 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 4.4 g (44 parts by mass), amine compound A to 1.5 g (15 parts by mass), and amine compound B to 0.6 g (6 parts by mass).

[0081] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 5 minutes. Furthermore, the Shore D hardness was 84 after 3 hours from the start of curing, and 85 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -7, b * The result was 25. These results are shown in Table 2.

[0082] Comparative Example 8 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 13.2 g (132 parts by mass), the amine compound A was changed to 0.3 g (3 parts by mass), and the amine compound B was changed to 0.6 g (6 parts by mass).

[0083] In the same manner as in Example 1, when the curing time at 23 °C was measured, it cured in 9 minutes. Also, the Shore D hardness 3 hours after the start of curing was 38, and the Shore D hardness 24 hours after the start of curing was 39. Furthermore, when the chromaticity of the cured product of the epoxy resin curable composition was measured, the chromaticity a * was -6, and b * was 16. These results are shown in Table 2.

[0084] Comparative Example 9 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 4.4 g (44 parts by mass), the amine compound A was changed to 0.3 g (3 parts by mass), and the amine compound B was changed to 0.6 g (6 parts by mass).

[0085] In the same manner as in Example 1, when the curing time at 23 °C was measured, it cured in 6 minutes. Also, the Shore D hardness 3 hours after the start of curing was 83, and the Shore D hardness 24 hours after the start of curing was 84. Furthermore, when the chromaticity of the cured product of the epoxy resin curable composition was measured, the chromaticity a * was -9, and b * was 26. These results are shown in Table 2.

[0086] Comparative Example 10 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 13.2 g (132 parts by mass), the amine compound A was changed to 0.3 g (3.0 parts by mass), and the amine compound B was changed to 0.1 g (1 part by mass). In the same manner as in Example 1, an epoxy resin curable composition was obtained.

[0087] In the same manner as in Example 1, when the curing time at 23 °C was measured, it cured in 17 minutes. Also, the Shore D hardness 3 hours after the start of curing was 41, and the Shore D hardness 24 hours after the start of curing was 44. Furthermore, when the chromaticity of the cured product of the epoxy resin curable composition was measured, the chromaticity a* -5, b * The result was 10. These results are shown in Table 2.

[0088] Comparative Example 11 An epoxy resin curable composition was obtained in the same manner as in Example 1, except that the thiol compound was changed to 4.4 g (44 parts by mass), amine compound A to 0.3 g (3 parts by mass), and amine compound B to 0.1 g (1 part by mass).

[0089] In the same manner as in Example 1, the curing time at 23°C was measured, and it cured in 12 minutes. Furthermore, the Shore D hardness was 10 after 3 hours from the start of curing, and 27 after 24 hours from the start of curing. In addition, the chromaticity of the cured epoxy resin composition was measured, and the chromaticity a * -6, b * The result was 12. These results are shown in Table 2.

[0090] [Table 1]

[0091] [Table 2]

Claims

1. An epoxy resin curable composition comprising an epoxy resin having two or more epoxy groups in one molecule, a thiol compound having two or more thiol groups in one molecule, an amine compound A having three or more primary amino groups and / or secondary amino groups, and an amine compound B having a tertiary amino group, wherein the number of moles of epoxy groups contained in the epoxy resin curable composition is Me, and the total number of moles of primary and secondary amino groups is M. １＋２ The number of moles of tertiary amino groups is M ３ In this case, the molar ratio M １＋２ / Me is between 0.11 and 0.5, and the molar ratio M ３ An epoxy resin curable composition having / Me = 0.005 to 0.

1.

2. The total number of moles of the primary and secondary amino groups, M. １＋２ The number of moles of the tertiary amino group M ３ Mole ratio M ３ / M １＋２ The epoxy resin curable composition according to claim 1, wherein the ratio is 0.04 to 1.

1.

3. The epoxy resin curable composition according to claim 1 or 2, wherein when the number of moles of thiol groups contained in the epoxy resin curable composition is Mt, the molar ratio Mt / Me of the number of moles of epoxy groups to Me is 0.1 to 0.

9.

4. The epoxy resin curable composition according to claim 1 or 2, wherein the thiol compound does not have a carbonyl group.

5. L of the cured product ＊ a ＊ b ＊ The chromaticity in the color system is such that a ＊ is from -10 to +10 and b ＊ is from -20 to +20. The epoxy resin curable composition according to claim 1 or 2.

6. The epoxy resin curable composition according to claim 1 or 2, wherein the curing time when 10 g of the epoxy resin curable composition is used and cured at 23°C and 50% RH is 1 to 15 minutes.

7. The epoxy resin curable composition according to claim 1 or 2, wherein when the epoxy resin curable composition is applied to a thickness of 6.0 mm or more and cured at 23°C and 50% RH, the Shore D hardness according to JIS K7215 is 75 or higher 3 hours after the start of curing, and the Shore D hardness according to JIS K7215 is 75 or higher 24 hours after the start of curing.

8. An epoxy resin curable composition according to claim 1 or 2, for use as an adhesive.

9. An adhesive containing the epoxy resin curable composition according to claim 1 or 2.

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